The invention relates to substituted or unsubstituted benzo-dioxinothiophenes, hereinafter referred to as 3,4-(1xe2x80x2,2xe2x80x2-benzo-dioxy)thiophene, a process for preparing it and its use for preparing electrically conductive oligomers or polymers. The invention further relates to oligomers or polymers which comprise these compounds as repeating unit.
Conductive organic polymers have a wide range of applications. An example which may be mentioned is their use for producing polymer batteries, diodes or transistors or solar cells. As conductive organic polymers, use is made of, for example, systems based on polyacetylene, poly(p-phenylene), polythiophene or polypyrrole.
There are some electrically conductive oligomers and polymers which can be prepared from thiophene derivatives. Previously known electrically conductive oligomers and polymers prepared from thiophene derivatives have aliphatic substituents. A particular example is provided by polymers based on 2,3-dihydrothieno[3,4-b][1,4]dioxin, which is also referred to as 3,4-ethylenedioxythiophene in the literature and is commercially available under the name BAYTRON(copyright) M from BAYER AG.
To be able to match the polymer properties to the respective requirements in a targeted way, it is necessary to have many suitable monomer building blocks available. It is therefore an object of the present invention to provide new thiophene derivatives and to find ways of preparing them.
The invention relates to a compound of the Formula (I): 
in which R1 and R2 are each, independently of one another, H, C1-C20-alkyl, C6-C10-aryl, C7-C12-aralkyl, C1-C18-alkoxy, C2-C 18-hydroxyal-kylenoxy, C2-C36-alkoxyalkylenoxy, hydroxyethyl, formyl, C2-C18-acyl, nitro, halogen, sulfo (xe2x80x94SO3H), cyano (xe2x80x94CN), carboxy (xe2x80x94COOH), C1-C18-alkoxy-carbonyl or trifluoromethyl, or together with the aromatic ring to which they are bound form a fused aromatic ring system, and X is N or Cxe2x80x94H.
The invention also relates to a process for preparing a compound of the Formula (I) that involves reacting a 3,4-dialkoxythiophene with a substituted or unsubstituted 1,2-dihydroxybenzene, and thereby making the compound of Formula (I).
The invention also relates to a process for making an electrically conductive polymer comprising polymerizing a compound of the Formula (I).
And the invention relates to an electrically conductive polymer comprising at least one repeating compound of the Formula (I).
The invention is further described in the following illustrative examples in which all parts and percentages are by weight unless otherwise indicated.